/Engine/Plugins/FX/Niagara/Source/NiagaraEditor/Public/NiagaraParameterMapHistory.h
For each variable that was found, identify the pins that read them from the map in order from first to last read. First of the pair has the read pin, second of the pair has the last set that wrote to the pin.
struct FReadHistory
TModuleScopedPi...
PreviousWritePin
TModuleScopedPi...
ReadPin